Hello,
I'm trying to get X to fire up a resolution beyond 640x480, but
although I've configured it to use 1024x768 (using dpkg-reconfigure),
it doesn't. I've installed 855wrap and have it running before X is
started, but it still runs in 640x480 mode. I have a Dell Inspiron
1150 with a 15' monitor, running Debian (sarge).

I own a Dell inspiron 510m with an i810 graphic chipset. I had the same
issue :

> (II) VESA(0): Not using mode "1024x768" (no mode of this name)

The fact is that the i810 driver uses the modes provided by the BIOS.
The BIOS is buggy and does not gives the right modes. A patch has been
available for a long time on the Intel website, but Dell does not care
about it. This topic has been discussed in the Dell forums.

Alain Poirier wrote a program to fake the driver. I use it on my 510m
and it works well.